This study has now been completed, and the results have been published (Pediatrics (1998), 102:6-13). This study involved the administration of recombinant G-CSF (or placebo) to newborn infants with neutropenia associated with either early-onset sepsis, maternal hypertension, late-onset sepsis, or necrotizing enterocolitis. The effects of treatment or placebo were assessed by measuring four outcome variables: blood neutrophil concentration, neutrophil production and function, severity of illness, and duration of illness. The study demonstrated that G-CSF was effective in correcting the neutropenia commonly found in septic newborn infants. In spite of correction of the neutropenia, there was little evidence of shortened Intensive Care Unit stays or of shortened total hospitalization time.